The present invention relates generally to storage systems and, more particularly, to method and apparatus to improve the efficiency in the use of resources in a data center.
Virtualization technology has become mature in data center. Virtualized server and virtualized application can be used without considering the limitation of physical resources such as server and storage. In the configuration of the data center, the components of the data center tend to have scale-out architecture. These components are connected by high-speed interconnect in general. Multiple data centers work together, forming a data center federation. In data center operation, Self Service Portal has become mainstream. Resource provisioning is done by service user, not IT administrator. Computing resource and storage resource provide resource pools. Service users can provision their resources from the pool in a flexible manner. For example, US2010/0040058 discloses a server resource pool in a virtualized environment. The frequency of deploy and the frequency of undeploy are increased, especially for test and development environment. US2010/0312893 also discloses a server resource pool in a virtualized environment. US2010/0058009 discloses storage resource pool in a storage system with automated resource allocation.
As to the progress of virtualized technology, over-provisioning has become common. A user can provision the resource more than the amount of a physical resource. This trend is supported by thin provisioning technology, for example. See, e.g., US2004/0162958 for automated on-line capacity expansion method for storage device. Other trends include hot migration of virtual server (e.g., VMware VMotion) and live migration of virtual machine disk file (e.g., VMware Storage VMotion). Some storage systems can use storage resources of other storage subsystems (e.g., External Storage Virtualization). US2004/0143832 discloses such an External Storage Virtualization function whereby a new storage unit is installed such that installation costs are suppressed and functions of the new storage unit can be utilized sufficiently. Some storage subsystems can lease resources of other storage temporarily (e.g., Enhancement of External Storage Virtualization). US2009/0157984 discloses such an Enhancement of External Storage Virtualization whereby a storage system provides virtual ports and is able to transfer the virtual ports among physical ports located on multiple storage control units making up the storage system.
Various resources coexist in one data center, creating a heterogeneous environment. For instance, various performances of IT resources are mixed in one data center. SSD is used as a new storage medium in addition to HDD. Connections of each resource may vary. Some resources are connected via high-speed interconnect; some are not. As to the automation of operation, resources are provisioned by the user, not the administrator. Performance tuning becomes automated.
The current approach has problems. Various operations are performed by various administrators and users such as provisioning, unprovisioning, adding the resources, hot migration of virtual server, and live migration of virtual machine file disk. The efficiency in the use of the resources in the data center drops. For example, some virtual machines may use storage resources of another rack. It is difficult to detect to monitor the virtualized environment. As a result, the following problems can occur: high performance resources are used for low priority application, some virtual machine cannot maintain SLO (Service Level Objective), the bandwidth of interconnect becomes short, etc.